To use Stackit you need a wallet connected to the BNB or Polygon chain (More chains soon). For information on MetaMask, visit their website. For information on Coinbase Wallet, visit their website. What is Wallet Connect?
MetaMask by default only supports the Ethereum network. However, when you connect MetaMask to Stackit, Stackit will automatically configure MetaMask to work with the chain you choose.
To perform transactions on BNB or Polygon chains, you will need BNB (BNB Chain) or Matic (Polygon) for gas.